IIDj, is collecting available measurements since March 26 of 2011 to provide a consistent and comprehensive Japan Radiation Map. Most of the data used are updated hourly, however some sources provide data in larger intervals or require manual transcription; in this case we can not guarantee regular updates. We do intentionally refrain from using any interpretative elements - such as thresholds or advisories. This needs to happen somewhere else with more competent people involved. Measurements are interchangeably provided in Gray/Sievert units at the source. The Japan Radiation Map shows all measurements in the nano Sievert/hour (nSv/h) unit - following the simplified equation where 1 Gray (Gy) = 1 Sievert (Sv).
IIDj, Institute for Information Design Japan | mail Disclaimer: IIDj has no past nor current business relations with any of the actors in the nuclear power industry.
This map shows ca 4,500 up-to-date radiation measurements, collected from various official sources. On roll-over information is provided for that particular location - radiation levels are visualized by the colored square's size. Locations marked with the + sign reveal more locations on zoom-in. Logging since march 2011, the accumulated data contains now 100,000,000+ records, available for research. Click here for more details.